If 5x + 3y = 27 and 6x - 2y = 10, find x and y
5x + 3y = 27 (1)6x - 2y = 10 (2)Rearrange (1) to make x the subject.Subtracting - 3y from both sides gives5x = 27 - 3yDivide both sides by 5 givesx = (27 - 3y)/5Substitute (1) into (2) gives6(27 - 3y)/5 - 2y = 10Multiple both sides by 5 gives6(27 - 3y) - 10y = 50Expand brackets162 - 18y - 10y = 50162 - 28y = 5028y = 112y = 112/28y = 4Now substitute y = 4 into (1)5x + 3(4) = 275x = 27 - 12x = 15/5x = 3
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